Twelve faculties, including Edinburgh and Glasgow bar associations, continue to oppose the government. The Scotsman understands Edinburgh lawyers are now planning a further escalation of industrial action.

That would see up to 40,000 legal aid cases a year put on hold where lawyers believe the fixed fee they receive is insufficient.

Suspects are entitled to legal representation and cases could be put on hold or discontinued if they cannot secure a lawyer.

An estimated 120,000 summary cases appear before sheriff and justice of the peace courts each year.

A source said: “Two thirds of those are covered by some form of legal aid, almost all of which are fixed fee. In half of cases the fixed fee is not enough.

“Cases where we reach the end of the line in terms of funding will be suspended with a debate fixed.

“We think other faculties will join us in this.”

There is a precedent. In Edinburgh last year, Jamie Marshall was allowed to withdraw his guilty plea to breaching curfew after the sheriff raised concerns about the fairness of a three-year antisocial behaviour order under the European Convention on Human Rights.

Marshall’s lawyer had received a fixed fee of £585, but legal expenses were expected to reach over £2,300.

With Marshall at risk of appearing undefended, Sheriff Nigel Morrison said: “He cannot receive a fair trial because there will be no one to represent him.”